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Cadillac Repair/1991 Cadillac, Deville 4.9 Liter V8

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Question
This has car a computer chip ignition system. We would like to know how to change it over to a regular ignition switch. We would also appreciate wiring diagrams on how to wire the regular ignition switch.The VIN. number for the vehicle is 1G6CD53B8M4298391 .                       
                                        Thanks,
                                     Gerald Carr

Answer
Hello,

Just a word of warning. It is not a good idea to place your VIN on the internet. Reason being is that if I were a bad guy and located where the car is kept (easy to do thanks to the Department of Motor Vehicles, I could go to a dealer and obtain an ignition key and door key. The ignition key would have the proper resistor code to operate the car.

Your car does not have a computer chip. It is merely a resistor. GM used 15 resistors in that year.

You do not have to change the ignition lock over to a non-chipped ignition lock. All you need to do is bypass the system which is rather easy because in my opinion of dealing with this system for 19 years, it is a piece of garbage and does not prevent theft, however what it does do is frustrate the owner when one of the two small wires running down the steering column from the ignition break internally. In fact, it is so problematic and antiquated that I get requests at my personal email robo14@aol.com sometimes as many as 10 a day to bypass this thing. I am now to the point I cannot even keep up with the requests and email.

The basic consept of bypass is simple, but there are variations between makes and models and every one bypassed HAS TO HAVE a hidden starter kill installed, because the car will get stolen in 30 seconds. Yes, old cars are stolen all the time! They blend in and hide in plain sight.

The reason you must install a hidden starter kill is because if you have comprehensive insurance (fire and theft) and you turn in a theft claim, you will be denied! Insurance companies are denying claims left and right across the US and their reason is because the claimed vehicles are equipped with so-called anti-theft systems from the factory. To them, any car with an anti-theft system that is stolen, is fraud because these vehicles are allegedly unstealable.

The way this works is that once the vehicle is reported stolen, their vendors (expert locksmiths) supply a list of vehicles and what type of anti-theft system they have. With this information, the insurance claims rep refers the claim to the special investigations unit. The special investigations unit farms it out to one of these locksmith experts to examine the ignition lock, which is deceptive anyway because it assumes the vehicle was driven from the theft scene. Of course if towed, the locksmith could not make money because it wouldn't matter the condition the ignition lock was in.

The other problem is that cars like your Cadillac, if the VATS (that's what your system is called) was not working or bypassed, the steering column can be defeated in 30 seconds with a screwdriver on the opposite side the ignition lock is located on the column. The locksmith would state that there is no damage to the ignition lock, so according to him, it was last operated with the proper key (yours). It doesn't matter if the left side of the steering column is broken and a key was no longer needed to unlock the wheel, shift the trans, or start the engine.

That is just one example and there are far too many of which the insured even if totally innocent is accused of faking the theft. Yes, there is fraud out there, and sometimes on the part of the insured, sometimes on the part of the expert and sometimes on the part of the insurance company. It is case by case.

Many in my field do not like me because our firm not only does examinations for insurance companies, but also insureds as well as consulting and supplying expert witness services. These experts don't being forced into proving the opinions they have. They don't like being embarrassed.

The term "Anti-theft" is misused because not one of these systems can stop theft. When working properly and when not easily bypassed, they are merely a theft deterrent. If the manufacturer (not the dealer) truly thought these anti-theft systems worked, they would warranty against theft.

If in the event you want to bypass the system, I will tell you the basics of doing it, however commonly I have to walk people through this and the professional installation of a hidden starter kill. That all takes time and I do charge a one time consulting fee.

This is addressed at http://www.autotheftexpert.com and go to the bypass security link.

Good Luck!

Rob  

Cadillac Repair

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Rob Painter

Expertise

Alarm system questions cannot be answered on this forum. These systems are not what I can answer. Without being physically at the vehicle and not knowing what kind of electrical service has been done on the vehicle, there is no possible way to give an accurate answer over the internet. My expertise is in Ignition/key based anti-theft systems. These issues include GM VATS (resistor chip in key blade) PASSLOCK (MRD)-ignition lock rotation based, no special ignition key and the PKIII Transponder (computer chip in key) systems. These systems are not alarm based and are integral with the starting of the engine. This is why I cannot diagnose alarm problems without physically looking at the vehicle: Alarm systems are a completely different annimal than ignition key/lock based anti-theft system. Many alarm questions come from vehicles 10 years old, and since older, many hands that had been involved over the years.I am an expert in all GM factory (ignition/key based)systems. Alarm system questions pose to many situations beyond my knowledge as to what has been done to the vehicle over the years. Some guy may have actually wired the stereo into the alarm system. Who knows? Over my past 30 years in vehicle wiring repair, I have seen unbelievable wiring disaters done by guys that consider themselves "mechanics." I have seen stereos and alarms intalled using surgical tape. I have seen modules burn up, un-fused circuits, wiring jambed between the doors and even lamp cord used for a starter kill. To answer alarm questions over the internet without examining the vehicle is like asking; What does it take to remove a dent?

Experience

Education/Credentials-ASE certified. 11 years with a GM dealer and 17 years with a repair facility dealing with only the repair of theft recovered vehicles.

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